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Full text of "Alaskan glacier studies of the National Geographic Society in the Yakutat Bay, Prince William Sound and lower Copper River regions"

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252
ALASKAN GLACIER STUDIES
dence of this advance is found in a comparison of the western margin of the glacier in the photographs taken from the same site in 1898 and 1905. The latter, by Grant, shows the ice edge a short distance farther west than in the 1898 picture by Schrader. This advance is also proved by other observations made in 1909, described below. Unfortunately Schrader's photograph does not extend far enough for us to compare the eastern margin of Shoup Glacier in 1898 and 1905. A comparison of Grant's 1905, 1908 and 1909 photographs of the two margins shows little, if any, retreat of the two edges.
Observations by the National Geographic Society's Expeditions. The National Geographic Society's expeditions spent August 19 and 20, 1909, and part of September 6, 1910, in a study of the Shoup Glacier, examinations being made of the eastern margin, the center of the ice front, and the southwest margin for some distance back from the glacier front. Photographs were taken from the site occupied by Schrader and Grant (Photo. Station A). The changes since Grant's last observations have been inappreciable. The topographic map reproduced as Fig. 24 was made in 1909 and bench marks were established on Photo. Station A and also on a point on the hillside to the west (Station C) from which transit readings were made as shown in Fig. 25. It is hoped that future observers may repeat the transit readings from these stations.
Transit Readings. Transit readings from Stations A and C, Shoup Glacier, August 20, 1909. Station A is an X on a rock on top of the first prominent spur south of the glacier on west side of Shoup Inlet at an elevation of 100 feet.
READINGS
Point Sighted	Ver.A	Ver.B	Angle from A-C
1. Station C	180 00'	00 00'	
2. Most easterly point of ice front.   (Same as			
No. 3, Sta. C)	148 51'	328 51'	31 09'
3. Projecting point of glacier at first bend back			
of glacier front on east side of glacier near			
stream outlet	157 48'	337 48'	22 12'
4. Southern point of glacier front on west side.			
(Same as No. 2, Sta. C)	89 10'	269 10'	90 50'
5 . Most western point of glacier	83 56'	263 56'	; 96 04'
Station C is an X on a bowlder located on the east side of Shoup Inlet at an elevation of 130 feet above'the fiord, and on the first large spur south of the glacier front close up to the edge of the thick alder.
READINGS
Point Sighted	Ver. A	Ver.B	Angle from A-C
1. Station A	00 00'	180 00'	
2. Southern point of glacier on west side	41 53'	221 53'	41 53'
8. Most easterly point of ice front visible from			
Sta. C	71 52'	251 52'	71 52'